Illustrative of prior art relating to the present invention, is U.S. Pat. No. 4,834,302 issued May 30, 1989, which patent discloses the general construction and operation of gasoline engine driven chipper/shredders including the use of flails or hammers pivotally mounted on a driven carrier to shred or otherwise comminute material fed through the inlet hopper of the apparatus. FIGS. 5 and 12 of U.S. Pat. No. 4,834,302 are of interest as being illustrative of known prior art, flail or hammer structures. Such prior art structures have been known to be a cause for reduced through-put of material to be shredded and were found to be generally expensive to manufacture and assemble.